This is assuming a highly doubtful starting point:

January 28th 00:00 GMT : Between 3,000 and 4,000 infected people, in different stages of incubation (1 to 14 days). Presenting symptoms : 37-38 cases.)

There is a lot of increasingly validated information out there demonstrating that there are 45,000 to as many as 140,000 infected people as of today. All due to intentional under-reporting or due to inability to diagnose actual cases (lack of supplies, staff, IT...).

Considering this, your scenario could be way too conservative.